Heretofore it has been common to house instrumentation in an instrument "can" which is closed by a bezel threaded to an upper threaded end of the instrument can. The bezel normally includes a transparent plastic sheet or panel bounded by a metallic rim, and it is through the transparent plastic panel that an instrument face of the instrument housed in the instrument can is viewed. Multiple spaced transparent plastic or glass panels, sheets or lens can be associated with a rim in an effort to create an "anti-fog" lens. Normally, these "stacks" utilize seals, adhesives and/or crimped metal between the rim and the transparent lens to create a chamber between the lens which is hermetically sealed against ambient moisture and fog, though most instrument covers thus manufactured fall short of this objective. Most conventional instrument covers do not use glass for the lens due to assembly problems and costs associated with the top or outermost lens falling out, cracking or otherwise being damaged. Thus, though glass lenses are highly coveted for instrument covers, the problems associated with assembly and repair dictate the utilization of transparent plastic for both the outer and inner lens of the instrument cover.